[RFCv2,06/13] iommufd: Make attach_handle generic

Commit Message

Nicolin Chen Jan. 11, 2025, 3:32 a.m. UTC

"attach_handle" was added exclusively for the iommufd_fault_iopf_handler()
used by IOPF/PRI use cases, along with the "fault_data". Now, the iommufd
version of sw_msi function will resue the attach_handle and fault_data for
a non-fault case.

Move the attach_handle part out of the fault.c file to make it generic for
all cases. Simplify the remaining fault specific routine to attach/detach.

Signed-off-by: Nicolin Chen <[e-mail]>
---
 drivers/iommu/iommufd/iommufd_private.h |  40 +-------
 drivers/iommu/iommufd/device.c          | 105 +++++++++++++++++++++
 drivers/iommu/iommufd/fault.c           | 120 +++---------------------
 3 files changed, 122 insertions(+), 143 deletions(-)

Patch

diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index b6d706cf2c66..063c0a42f54f 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -472,42 +472,12 @@  void iommufd_fault_destroy(struct iommufd_object *obj);
 int iommufd_fault_iopf_handler(struct iopf_group *group);
 
 int iommufd_fault_domain_attach_dev(struct iommufd_hw_pagetable *hwpt,
-				    struct iommufd_device *idev);
+				    struct iommufd_device *idev,
+				    bool enable_iopf);
 void iommufd_fault_domain_detach_dev(struct iommufd_hw_pagetable *hwpt,
-				     struct iommufd_device *idev);
-int iommufd_fault_domain_replace_dev(struct iommufd_device *idev,
-				     struct iommufd_hw_pagetable *hwpt,
-				     struct iommufd_hw_pagetable *old);
-
-static inline int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt,
-					     struct iommufd_device *idev)
-{
-	if (hwpt->fault)
-		return iommufd_fault_domain_attach_dev(hwpt, idev);
-
-	return iommu_attach_group(hwpt->domain, idev->igroup->group);
-}
-
-static inline void iommufd_hwpt_detach_device(struct iommufd_hw_pagetable *hwpt,
-					      struct iommufd_device *idev)
-{
-	if (hwpt->fault) {
-		iommufd_fault_domain_detach_dev(hwpt, idev);
-		return;
-	}
-
-	iommu_detach_group(hwpt->domain, idev->igroup->group);
-}
-
-static inline int iommufd_hwpt_replace_device(struct iommufd_device *idev,
-					      struct iommufd_hw_pagetable *hwpt,
-					      struct iommufd_hw_pagetable *old)
-{
-	if (old->fault || hwpt->fault)
-		return iommufd_fault_domain_replace_dev(idev, hwpt, old);
-
-	return iommu_group_replace_domain(idev->igroup->group, hwpt->domain);
-}
+				     struct iommufd_device *idev,
+				     struct iommufd_attach_handle *handle,
+				     bool disable_iopf);
 
 static inline struct iommufd_viommu *
 iommufd_get_viommu(struct iommufd_ucmd *ucmd, u32 id)
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index dfd0898fb6c1..38b31b652147 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -352,6 +352,111 @@  iommufd_device_attach_reserved_iova(struct iommufd_device *idev,
 	return 0;
 }
 
+/* The device attach/detach/replace helpers for attach_handle */
+
+static int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt,
+				      struct iommufd_device *idev)
+{
+	struct iommufd_attach_handle *handle;
+	int rc;
+
+	if (hwpt->fault) {
+		rc = iommufd_fault_domain_attach_dev(hwpt, idev, true);
+		if (rc)
+			return rc;
+	}
+
+	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
+	if (!handle) {
+		rc = -ENOMEM;
+		goto out_fault_detach;
+	}
+
+	handle->idev = idev;
+	rc = iommu_attach_group_handle(hwpt->domain, idev->igroup->group,
+				       &handle->handle);
+	if (rc)
+		goto out_free_handle;
+
+	return 0;
+
+out_free_handle:
+	kfree(handle);
+	handle = NULL;
+out_fault_detach:
+	if (hwpt->fault)
+		iommufd_fault_domain_detach_dev(hwpt, idev, handle, true);
+	return rc;
+}
+
+static struct iommufd_attach_handle *
+iommufd_device_get_attach_handle(struct iommufd_device *idev)
+{
+	struct iommu_attach_handle *handle;
+
+	handle =
+		iommu_attach_handle_get(idev->igroup->group, IOMMU_NO_PASID, 0);
+	if (IS_ERR(handle))
+		return NULL;
+	return to_iommufd_handle(handle);
+}
+
+static void iommufd_hwpt_detach_device(struct iommufd_hw_pagetable *hwpt,
+				       struct iommufd_device *idev)
+{
+	struct iommufd_attach_handle *handle;
+
+	handle = iommufd_device_get_attach_handle(idev);
+	iommu_detach_group_handle(hwpt->domain, idev->igroup->group);
+	if (hwpt->fault)
+		iommufd_fault_domain_detach_dev(hwpt, idev, handle, true);
+	kfree(handle);
+}
+
+static int iommufd_hwpt_replace_device(struct iommufd_device *idev,
+				       struct iommufd_hw_pagetable *hwpt,
+				       struct iommufd_hw_pagetable *old)
+{
+	struct iommufd_attach_handle *old_handle =
+		iommufd_device_get_attach_handle(idev);
+	struct iommufd_attach_handle *handle;
+	int rc;
+
+	if (hwpt->fault) {
+		rc = iommufd_fault_domain_attach_dev(hwpt, idev, !old->fault);
+		if (rc)
+			return rc;
+	}
+
+	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
+	if (!handle) {
+		rc = -ENOMEM;
+		goto out_fault_detach;
+	}
+
+	handle->idev = idev;
+	rc = iommu_replace_group_handle(idev->igroup->group, hwpt->domain,
+					&handle->handle);
+	if (rc)
+		goto out_free_handle;
+
+	if (old->fault)
+		iommufd_fault_domain_detach_dev(old, idev, old_handle,
+						!hwpt->fault);
+	kfree(old_handle);
+
+	return 0;
+
+out_free_handle:
+	kfree(handle);
+	handle = NULL;
+out_fault_detach:
+	if (hwpt->fault)
+		iommufd_fault_domain_detach_dev(hwpt, idev, handle,
+						!old->fault);
+	return rc;
+}
+
 int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
 				struct iommufd_device *idev)
 {
diff --git a/drivers/iommu/iommufd/fault.c b/drivers/iommu/iommufd/fault.c
index 06aa83a75e94..1d9bd3024b57 100644
--- a/drivers/iommu/iommufd/fault.c
+++ b/drivers/iommu/iommufd/fault.c
@@ -60,42 +60,17 @@  static void iommufd_fault_iopf_disable(struct iommufd_device *idev)
 	mutex_unlock(&idev->iopf_lock);
 }
 
-static int __fault_domain_attach_dev(struct iommufd_hw_pagetable *hwpt,
-				     struct iommufd_device *idev)
-{
-	struct iommufd_attach_handle *handle;
-	int ret;
-
-	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
-	if (!handle)
-		return -ENOMEM;
-
-	handle->idev = idev;
-	ret = iommu_attach_group_handle(hwpt->domain, idev->igroup->group,
-					&handle->handle);
-	if (ret)
-		kfree(handle);
-
-	return ret;
-}
-
 int iommufd_fault_domain_attach_dev(struct iommufd_hw_pagetable *hwpt,
-				    struct iommufd_device *idev)
+				    struct iommufd_device *idev,
+				    bool enable_iopf)
 {
-	int ret;
+	int rc = 0;
 
 	if (!hwpt->fault)
 		return -EINVAL;
-
-	ret = iommufd_fault_iopf_enable(idev);
-	if (ret)
-		return ret;
-
-	ret = __fault_domain_attach_dev(hwpt, idev);
-	if (ret)
-		iommufd_fault_iopf_disable(idev);
-
-	return ret;
+	if (enable_iopf)
+		rc = iommufd_fault_iopf_enable(idev);
+	return rc;
 }
 
 static void iommufd_auto_response_faults(struct iommufd_hw_pagetable *hwpt,
@@ -127,86 +102,15 @@  static void iommufd_auto_response_faults(struct iommufd_hw_pagetable *hwpt,
 	mutex_unlock(&fault->mutex);
 }
 
-static struct iommufd_attach_handle *
-iommufd_device_get_attach_handle(struct iommufd_device *idev)
-{
-	struct iommu_attach_handle *handle;
-
-	handle = iommu_attach_handle_get(idev->igroup->group, IOMMU_NO_PASID, 0);
-	if (IS_ERR(handle))
-		return NULL;
-
-	return to_iommufd_handle(handle);
-}
-
 void iommufd_fault_domain_detach_dev(struct iommufd_hw_pagetable *hwpt,
-				     struct iommufd_device *idev)
+				     struct iommufd_device *idev,
+				     struct iommufd_attach_handle *handle,
+				     bool disable_iopf)
 {
-	struct iommufd_attach_handle *handle;
-
-	handle = iommufd_device_get_attach_handle(idev);
-	iommu_detach_group_handle(hwpt->domain, idev->igroup->group);
-	iommufd_auto_response_faults(hwpt, handle);
-	iommufd_fault_iopf_disable(idev);
-	kfree(handle);
-}
-
-static int __fault_domain_replace_dev(struct iommufd_device *idev,
-				      struct iommufd_hw_pagetable *hwpt,
-				      struct iommufd_hw_pagetable *old)
-{
-	struct iommufd_attach_handle *handle, *curr = NULL;
-	int ret;
-
-	if (old->fault)
-		curr = iommufd_device_get_attach_handle(idev);
-
-	if (hwpt->fault) {
-		handle = kzalloc(sizeof(*handle), GFP_KERNEL);
-		if (!handle)
-			return -ENOMEM;
-
-		handle->idev = idev;
-		ret = iommu_replace_group_handle(idev->igroup->group,
-						 hwpt->domain, &handle->handle);
-	} else {
-		ret = iommu_replace_group_handle(idev->igroup->group,
-						 hwpt->domain, NULL);
-	}
-
-	if (!ret && curr) {
-		iommufd_auto_response_faults(old, curr);
-		kfree(curr);
-	}
-
-	return ret;
-}
-
-int iommufd_fault_domain_replace_dev(struct iommufd_device *idev,
-				     struct iommufd_hw_pagetable *hwpt,
-				     struct iommufd_hw_pagetable *old)
-{
-	bool iopf_off = !hwpt->fault && old->fault;
-	bool iopf_on = hwpt->fault && !old->fault;
-	int ret;
-
-	if (iopf_on) {
-		ret = iommufd_fault_iopf_enable(idev);
-		if (ret)
-			return ret;
-	}
-
-	ret = __fault_domain_replace_dev(idev, hwpt, old);
-	if (ret) {
-		if (iopf_on)
-			iommufd_fault_iopf_disable(idev);
-		return ret;
-	}
-
-	if (iopf_off)
+	if (handle)
+		iommufd_auto_response_faults(hwpt, handle);
+	if (disable_iopf)
 		iommufd_fault_iopf_disable(idev);
-
-	return 0;
 }
 
 void iommufd_fault_destroy(struct iommufd_object *obj)